A reputed gang member is behind bars, accused of raping a woman with a heart condition at her southwest Houston apartment in May, Harris County prosecutors said.

The victim, 67, told police that someone knocked on her door on May 14, and thinking it was her neighbor bringing fruit and groceries, she answered, according to a criminal complaint filed Aug. 27.

A man wearing a navy-blue 'do rag' and carrying a backpack forced his way into the apartment on Wallingford Drive, struck her in the head with his hand and sexually assaulted her, Houston police said.

After the assault, the victim asked the assailant for a nitroglycerin pill she had in the apartment, and he handed the medication to her.

When a noise outside the apartment drew his attention, she told him, "That is my roomate, she is coming back," the complaint states.

Before he fled on foot, the stranger told her, "I will kill you and kill her too. I will be back."

When she realized the suspect wasn't returning, the victim ran to a neighbor's for help. She was treated at Memorial Hermann-Memorial City Hospital, where DNA evidence was collected from the assault, according to police.

John Hayward Milstead, 27, of Missouri City, is being held at the Harris County Jail in lieu of a $100,000 bond, charged with two felony counts of aggravated sexual assault of an elderly or handicapped person, court records show.

He is scheduled to appear Oct. 10 before state District Judge Denise Bradley of the 262nd District Court.

Investigators said that Milstead is a member of the 52 Hoover Crips, a Houston street gang.